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bioRxiv · 10.1101/2020.04.15.043018

Uneven distribution of Purkinje cell injury in the cerebellar vermis of term neonates with hypoxic-ischemic encephalopathy

Abstract

IntroductionIn term neonates with hypoxic-ischemic encephalopathy (HIE), cerebellar injury is becoming more and more acknowledged. Animal studies demonstrated that Purkinje cells (PCs) are especially vulnerable for hypoxic-ischemic injury. In neonates, however, the extent and pattern of PC injury has not been investigated. The aim of this study was to determine the distribution of PC injury in the cerebellar vermis of term born neonates with HIE. MethodsTerm born neonates with HIE that underwent post-mortem autopsy of the cerebellar vermis were included. Haematoxylin & Eosin (H&E) stained sections of the vermis were used to determine total PC count and morphology (normal, abnormal or non-classified) at the bases and crown of the folia and of the lobules in both the anterior and posterior lobes. Differences in PC count and PC morphology between the anterior and posterior lobe and between the bases and crown were calculated using the paired samples T-test or Wilcoxon-signed rank test. ResultsThe total number of PCs were significantly higher at the crown compared to the bases (p<0.001) irrespective of the precise location. Besides, PCs at the bases more often had an abnormal morphology. No significant difference between the total number of PCs in the anterior and posterior lobe was observed. ConclusionThe abnormal PC count and morphology in term neonates with HIE resembles supratentorial ulegyria.

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BibTeXRIS

Annink, K. V., van Leeuwen, I. C. E., van der Aa, N. E., Alderliesten, T., Groenendaal, F., Jellema, R. K., Nijboer, C. H. A., Nikkels, P. G. J., Lammens, M., Benders, M. J. N. L., Hoebeek, F. E., Dudink, J.. 2020-04-17. Uneven distribution of Purkinje cell injury in the cerebellar vermis of term neonates with hypoxic-ischemic encephalopathy. https://doi.org/10.1101/2020.04.15.043018

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